Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for RSVP Interface-Based Receiver Proxy

You must configure an IP address and enable Resource Reservation Protocol (RSVP) on one or more interfaces on at least two neighboring routers that share a link within the network.

Restrictions for RSVP Interface-Based Receiver Proxy

Filtering using access control lists (ACLs), application IDs, or other mechanisms is not supported.

A provider edge (PE) router cannot switch from being a proxy node to a transit node for a given flow during the lifetime of the flow.

Information About RSVP Interface-Based Receiver Proxy

Feature Overview of RSVP Interface-Based Receiver Proxy

The RSVP Interface-Based Receiver Proxy feature allows you to use RSVP to signal reservations and guarantee bandwidth on behalf of a receiver that does not support RSVP by terminating the PATH message and generating a RESV message in the upstream direction on an RSVP-capable router on the path to the endpoint. An example is a video-on-demand flow from a video server to a set-top box, which is a computer that acts as a receiver and decodes the incoming video signal from the video server.

Because set-top boxes may not support RSVP natively, you cannot configure end-to-end RSVP reservations between a video server and a set-top box. Instead, you can enable the RSVP interface-based receiver proxy on the router that is closest to that set-top box.

The router terminates the end-to-end sessions for many set-top boxes and performs admission control on the outbound (or egress) interface of the PATH message, where the receiver proxy is configured, as a proxy for Call Admission Control (CAC) on the router-to-set-top link. The RSVP interface-based receiver proxy determines which PATH messages to terminate by looking at the outbound interface to be used by the traffic flow.

You can configure an RSVP interface-based receiver proxy to terminate PATH messages going out a specified interface with a specific action (reply with RESV, or reject). The most common application is to configure the receiver proxy on the edge of an administrative domain on interdomain interfaces. The router then terminates PATH messages going out the administrative domain while still permitting PATH messages transitioning through the router within the same administrative domain to continue downstream.

The router terminates the end-to-end sessions for many set-top boxes, with the assumption that the links further downstream (for example, from the DSLAM to the set-top box) never become congested or, more likely, in the case of congestion, that the voice and video traffic from the router gets the highest priority and access to the bandwidth.

Benefits of RSVP Interface-Based Receiver Proxy

Before the RSVP Interface-Based Receiver Proxy feature was introduced, you had to configure a receiver proxy for every separate RSVP stream or set-top box. The RSVP Interface-Based Receiver Proxy feature allows you to configure the proxy by outbound interface. For example, if there were 100 set-top boxes downstream from the proxy router, you had to configure 100 proxies. With this enhancement, you configure only the outbound interfaces. In addition, the receiver proxy is guaranteed to terminate the reservation only on the last hop within the core network. Nodes that may function as transit nodes for some PATH messages but should proxy others depending on their placement in the network can perform the correct functions on a flow-by-flow basis.

Configuring PATH Messages from a Headend Router to Tailend Routers to Test the Receiver Proxy

Note

If you do not have another headend router generating RSVP PATH messages available, configure one in the network for the specific purpose of testing RSVP features such as the receiver proxy. Note that these commands are not expected (or supported) in a final deployment.

The following example configures four PATH messages from the headend router (Router 1) to the tailend routers (Routers 3 and 4):

The following example verifies that a PATH message has been terminated by a receiver proxy configured to reply.

Note

A receiver proxy that is configured to reject does not cause any state to be stored in the RSVP database; therefore, this show command does not display these PATH messages. Only one PATH message is shown.

RFCs

RFC

Title

RFC 2205

Resource ReSerVation Protocol (RSVP)

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

Feature Information for RSVP Interface-Based Receiver Proxy

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Table 1 Feature Information for RSVP Interface-Based Receiver Proxy

Feature Name

Releases

Feature Information

RSVP Interface-Based Receiver Proxy

Cisco IOS XE Release 2.6

Cisco IOS XE Release 3.8S

The RSVP Interface-Based Receiver Proxy feature lets you configure a proxy router by outbound interface instead of configuring a destination address for each flow going through the same interface.

The following commands were introduced or modified: iprsvpbandwidth,iprsvplisteneroutbound, showiprsvplisteners,showiprsvpreservation,showiprsvpsender.

In Cisco IOS XE Release 3.8S, support was added for the Cisco ASR 903 Router.

Glossary

flow--A stream of data traveling between two endpoints across a network (for example, from one LAN station to another). Multiple flows can be transmitted on a single circuit.

PErouter--provider edge router. A router that is part of a service provider’s network and is connected to a customer edge (CE) router.

proxy--A component of RSVP that manages all locally originated and terminated state.

receiverproxy--A configurable feature that allows a router to proxy RSVP RESV messages for local or remote destinations.

RSVP--Resource Reservation Protocol. A protocol for reserving network resources to provide quality of service guarantees to application flows.

set-top box--A computer that acts as a receiver and decodes the incoming signal from a satellite dish, a cable network, or a telephone line.